1. Field of the Invention
The present invention relates to an image pickup apparatus capable of interchanging lenses, and relates to a lens mount for the image pickup apparatus.
2. Description of the Related Art
There has been known an image pickup apparatus having an image pickup apparatus body to which an interchangeable lens such as a fixed focal lens, zoom lens, wide-angle lens, telephoto lens, or macro lens can be detachably mounted to make it possible to perform photographing while changing the angle of view, depth of focus, F value, etc. For such type of image pickup apparatus, a bayonet type lens mount has widely been used.
Generally, in the bayonet type lens mount, the interchangeable lens and the image pickup apparatus body are rotated relative to each other in a state that a mount face of the interchangeable lens abuts against amount face of the image pickup apparatus body, thereby engaging pawled portions of these mount faces with one another. At this time, the interchangeable lens is urged toward the image pickup apparatus body by spring members, which are built in the image pickup apparatus body, and is held by the image pickup apparatus body (see, for example, Japanese Laid-open Patent Publication No. 2004-102005).
However, since the interchangeable lens is held by urging forces of the spring members, a problem is posed that the interchangeable lens is rattled by an amount of flexure of the spring members. In particular, a large-sized interchangeable lens is liable to be rattled at the lens mount, resulting in a fear that the quality of photographed image is lowered.
There is also known an image pickup apparatus in which an electrical signal is exchanged between an image pickup apparatus body and an interchangeable lens to control the drive of the interchangeable lens. For power supply and for signal communication, contact terminal portions are provided in the image pickup apparatus body and in the interchangeable lens.
For example, in interchangeable lenses having a lens mount detachably mountable to a mount of an image pickup apparatus body by being rotated about an optical axis relative to the mount of the image pickup apparatus body, there is known an interchangeable lens having a connector configured to be connected with a connector of the image pickup apparatus body (see, Japanese Patent Publication No. 3733240). This interchangeable lens includes a contact support plate fixed with contact pins, a conductor support plate having a conduction part, and an elastic member for causing the conduction part to be in press-contact with the contact pins. The contact support plate, the conductor support plate, and the elastic member each have an end face formed into a comb-teeth shape.
In the case of a mount structure where the interchangeable lens is mounted to and dismounted from the image pickup apparatus body by being linearly moved relative to the image pickup apparatus body without being rotated, however, contact terminal portions of the image pickup apparatus body and contact terminal portions of the interchangeable lens do not rub against one another when the interchangeable lens is mounted to or dismounted from the image pickup apparatus body. Accordingly, a so-called self-cleaning operation is not performed, resulting in a fear that a contact failure can occur.